Which individual is at increased risk for hypocalcemia due to a medical condition?

The adolescent living with renal failure is at increased risk for hypocalcemia due to the impaired ability of the kidneys to filter blood and manage electrolyte balance effectively. In renal failure, the kidneys may not convert enough vitamin D to its active form, which is essential for calcium absorption from the intestine. Additionally, the kidneys also struggle to excrete phosphorus, leading to elevated phosphorus levels that can bind to calcium, further decreasing the levels of free calcium in the serum. This combination of factors creates a significant risk for hypocalcemia in individuals with renal failure.

In contrast, an athlete with a high calcium diet is more likely to maintain adequate calcium levels due to increased intake. An elderly person taking supplements may also be managing their calcium levels actively, and a healthy adult without health issues is generally not at risk for low calcium levels. Hence, the individual with renal failure is distinctly positioned with specific complications that can lead to decreased calcium levels in the body.